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Demand Duo Commercial Hybrid System Offers the Best of Both Worlds

by | Nov 8, 2015

Old style tank water heaters are inefficient, requiring high amounts of energy to maintain temperatures in a large storage tank, especially during heavy usage periods. Temperature loss due to long distribution lines adds to the energy cost. Tankless water heaters are more efficient by heating water on demand where needed, but expensive and difficult to maintain in large commercial facilities with many hot water distribution points. The demand duo commercial hybrid system combines the best features of tank-style water heaters and tankless systems by marrying a high-efficiency tankless heater to a smaller storage tank.

The smaller, insulated tank prevents hot water shortages during peak use periods. The tankless style heater piggybacked to the tank provides efficient, on-going heating of the water entering the tank. By heating the water before it enters the tank, it does not drag down the temperature of the water in the tank. Maintaining a constant temperature in the tank then takes much less energy. According to Rinnai, the manufacturer based in Peachtree City, Georgia, the Rinnai Demand Duo C199 has a 96% thermal efficiency and is Commercial Energy Star certified.

“The Demand Duo Commercial Hybrid System was created with the priorities of commercial customers in mind. The unique system approach provides a direct replacement for their aging, existing systems with the latest technologies in one product,” said James York, Vice President of Engineering for Rinnai America Corporation. “Combining the high efficiency of the C199 with a 119-gallon storage tank creates a solution leveraging the benefits of both tankless and tank, meaning customers win.”

If you have a large, multi-tank water heating system, the Demand Duo C199 water heater replaces old, inefficient tanks individually regardless of brand. One Demand Duo C199 will replace two or three tankless water heaters, depending on your application. To explore ways you can improve your commercial hot water system contact a Waterheaters.com authorized Rinnai Applications Engineer about sizing and space requirements.